1. Field of the Invention
The invention relates to a disk-reproducing apparatus for reproducing data on a disk such as CD-ROM and DVD (digital video disk).
2. Description of the Related Art
The disk-reproducing apparatus has a driving mechanism to spin a disk at high speed. This disk drive mechanism comprises a motor section and a disk-chucking section for centering and chucking the disk. The motor section includes a shaft, a bearing, a plurality of electromagnetic coils, a rotor and a plurality of magnets fixed to the rotor. The disk-chucking section includes a table on which the disk is placed, a centering part which mates with the center hole of the disk to make centering of the disk, and a means for chucking the disk with the table.
The table and the centering part of the disk-chucking section have a shaft hole, in which one end of the shaft protruding from the rotor of the motor section is press-fitted. Thus, the motor section is connected with the disk-chucking section.
In developing a disk-reproducing apparatus, which is mounted on a compact information-processing device such as a [note] notebook type personal computer, it is necessary to make the overall thickness of the disk drive mechanism small. To produce a thin disk drive mechanism, vigorous efforts have been made vigorously to reduce the thickness of various parts.
But, with the existing part fabricating technology, it is hard to produce small parts with high accuracy. If the parts which configure the disk drive mechanism are not fabricated accurately, a phenomenon of vertically vibrating a disk (face-vibrating phenomenon), which is caused while the disk is being spun, becomes extreme, resulting in lowered performance of the optical pickup to follow tracks. And, the rotor supported by the shaft and the disk-chucking section have an increased instability as the shaft hole in which the shaft is press-fitted becomes shorter. Under such conditions, the limit for reducing the overall thickness of the disk drive mechanism by reducing the thickness of the respective parts is almost reached.
Besides, such a disk drive mechanism tends to have unevenness in assembling the respective parts accurately. Especially, if the press fitting of the shaft into the shaft hole of the disk-chucking section is variable in length, respective disk-reproducing apparatuses have a different length from the disk to the lens of the optical pickup. Thus, the ability to follow the tracks with the optical pickup is adversely affected.
It is an object of the invention to provide a disk-reproducing apparatus, which is produced with ease, with high dimensional accuracy and made thin.
It is another object of the invention to provide a disk reproducing apparatus, which does not generate heavy face disk vibration and which excels in operational reliability such as the ability to follow tracks with an optical pickup.
It is also another object of the invention to provide a disk-reproducing apparatus having a highly accurate flat disk-mounting table.
To achieve the above objects, the disk-reproducing apparatus of the invention is configured as described below. Specifically, the invention relates to a disk-reproducing apparatus having a rotor of a disk motor and a disk-chucking section formed into one body, which comprises a base which supports a bearing and electromagnetic coils; a shaft which is rotatably supported by the bearing; a rotor which is connected with the shaft and has a disk-mounting face on which a disk is placed; magnets which are fixed to the rotor; and a disk-chucking section which is formed integral with the rotor to make centering and chucking of the disk which is placed on the disk-mounting face of the rotor.
The disk-reproducing apparatus of the invention has the rotor having a face, on which a disk is placed, and the disk-chucking section formed into one body instead of separate parts, so that its overall height can be made small, and a high dimensional accuracy can be obtained. Thus, a thin disk-reproducing apparatus, which does not cause heavy face disk vibrations, can be provided.
And, the disk-reproducing apparatus of the invention has the rotor, which is formed of a first portion to which the magnets are fixed and a second portion, which is formed integral with the table, and the first portion being connected with the second portion. Thus, the respective parts can be made to have a simple shape, and higher dimensional accuracy can be obtained.
To achieve the objects described above, the disk-reproducing apparatus according to another aspect of the invention is configured as described below. Specifically, the invention relates to a disk-reproducing apparatus having a rotor of a disk motor and a disk-chucking section formed into one body, which comprises a base which supports a bearing and electromagnetic coils; a shaft which is rotatably supported by the bearing; a rotor which is formed integral with the shaft and has a disk-mounting face on which a disk is placed; magnets which are fixed to the rotor; and a disk-chucking section which is formed integral with the rotor and makes centering and chucking the disk placed on the disk-mounting face of the rotor.
Since the rotor having the face on which the disk is placed, the disk-chucking section and the shaft are formed into one body, the disk-reproducing apparatus of the invention does not require the extra step of press fitting the shaft. Therefore, the disk drive mechanism be more readily assembled readily and a length between the lens of an optical pickup and a disk can be made constant in every device. In addition, the disk-reproducing apparatus thus provided has excellent optical pickup.